Air conditioning system



Aug. 27,' 1940.

w. GOODMAN AIR yCONDITIONING SYSTEM Original Filed July 1l, 1932Patented Aug. 27, 1940 UNITED STATES AIR CONDITIONING SYSTEM WilliamGoodman, La Crosse, Wis., assigner to General Motors Corporation,Dayton, Ohio, a

corporation of Delaware Original application July 11, 1932, Serial No.

621,944. Renewed August10, 1935. Divided and this application November3, 1936, Serial No.

This invention relates to air conditioning systems and more particularlyto a system especially adapted for conditioning the air in a building orthe like, in accordance with the requirements in the building.

This application is a division of my cepending application for LettersPatent, Serial No. 621,- 944, led July 11, 1932, renewed August 10,1935, now Patent No. 2,072,166.

One of the objects of my invention is to provide an air conditioningsystem embodying a source 0f supply of conditioned air and to maintaindry bulb temperature and relative humidity in a building or the likepursuant to the requirements or conditions and notwithstanding varyingsensible heat and moisture gains o'r losses in the building. v

If no sensible heat is added to saturated air leaving a conditioner, itsdry bulb and dew point temperatures are the same. As conditioned airenters a room, it is heated by the sensible heat liberated in the roomand the air also absorbs moisture liberated in the room. Under extremeconditions, if the volume of low temperature saturated air supplied to aroom to absorb all of the moisture being liberated is so great that thesensible heat liberated in the room is insuicient in quantity to heatthe air supply to the desired dry bulb temperature, I have found thatthis dry bulb temperature gradually falls below that desired to bemaintained. Under such conditions sensible heat must be added to the airsupply in an amount suicient to reduce the sensible heat absorbingcapacity of the air so that the sensiblel heat liberated in the roommerely heats the air to the desired temperature and this in" no wayimpairs the moisture absorbing capacity of the air supply. Hence,another object of my invention is to provide an air conditioning systemwherein sensible heat may be added to the air and to add this sensibleheat without the necessity of increasing the capacity of therefrigerating device of the system over that which would be required ifno sensible heat were added.

A still further object is to extract heat from air entering the airconditioner and to add this extracted heat to air discharged from theair conditioner as required.

Selected embodiments of the invention are illustrated in theaccompanying drawing wherein The figure of the drawing is a partlydiagrammatic View illustrating a system of supplying this conditionedair to a building.

In the arrangement illustrated an inlet conduit |28 is provided whichmay lead from a operated. The fluid or secondary refrigerant in sClaims. (01; 251-3) source of fresh air, a return air duct, or both. Anevaporator or calefactory member |29 is provided and air flowing throughthe conduit |28 passes through this evaporator. A dehumidifierconsisting of the refrigerating coil |30 for primary refrigerantseparate from the secondary refrigerant and an eliminator |3| isarranged between the inlet conduit |28 and the outlet conduit |32 whichleads to a fan housing |33 and a fan mounted on the shaft |34 draws airthrough the conduit 10 |28 past the evaporator |29, refrigerating coil|39, and eliminator |3| and discharges the air into a distributing duct|35. In the distributing duct |35 is a condenser or calefactory member35 having a return pipe |31 leading therefrom. Leading from the upperpart of the evaporator |29 is a pipe |31' which leads into a tank |38. Apipe |39 leads from the tank to the condenser |35. In the tank |38 is acold water coil |40 including an inlet pipe |4| and an outlet pipe |42.An automatic valve |43 is provided in the inlet pipe |4| and is actuatedby an operating device |44 which may be controlled by a thermostatarranged in the room to which air is being supplied or in the supplyduct or return air duct to be aifected' by the air temperature so thatif the temperature of the air rises the valve |43 will open to permitwater to flow through the coil |40 and when the temperature falls thevalve |43 will tend to close. Also arranged in the tank |38 is a steamcoil |45 including an inlet line |45 and an outlet line |41. A valve |48is provided in the inlet line |48 and is actuated by an operating device|49 which in turn may be regulated in thesame manner as the thermostaticdevice |44. A return pipe |50 leads from the tank |38 to a T-iitting|5|. A pipe line |52 leads from the T-tting |5| to a pump |53 operatedby an electric motor |54 or the like. The return line |31 terminates ina T-tting |55 and a pipe |56 extends between the T-ttings |5| and |55and has a valve |51 therein. A pipe |58 leads from the bottom of theevaporator |49 to a T-litting |59 and a pipe extends between the pump|53 and the T-fitting |59. Another pipe |5| extends between the T-ttings|59 and |55.

The water coil |49 and the 'steam coil |45 are Anot used at the sametime, the water coil being during the winter when the heat ow is out ofthe room. When the Water coil |40 is being used, the valve |57 is openand the pump |53 is not liquid state substantially fills the evaporator|29 and seeks a corresponding level in the pipes |50 and |31.evaporator, the liquid is converted into a vapor state and passes intothe pipe |31' and is discharged into the tank |38. From the tank |38 thevapor flows through the pipe |39 to the condenser |36 and the cooled airflowing through the duct flows through the condenser |36 and takes upsensible heat and the vapor reverts to a liquid state and returnsthrough the pipe |37. As the temperature rises, the control mechanismregulating the operating device |44 opens the valve |43 whereupon coldwater flows through the coil |40. This cold water condenses vapor in thetank |38 which reverts to a liquid state and returns through pipe |50.The amount of cold water flowing through the coil determines thequantity of vapor passing to the condenser |36 and by alternate openingand closing of the valve |43, as brought about by the operating device|44, a state of equilibrium is reached and this is maintained untilthere is a variation in the temperature or humidity of the air passingthrough the duct |35 or in the room or rooms to which this air issupplied. Thus by controlling the flow of water through the coil |40,the amount of sensible heat added to the air flowing through the duct|35 may be accurately regulated.

When the steam coil |45 is to be employed, the valve |5`| is closed andthe pump |53 acts to withdraw liquid from the pipes |31, IGI, |58, and|60, and forces the liquid through the pipe |52, T- fitting |5| and pipe|50 into the tank |38. This liquid is heated by the steam or otherheating medium flowing through the coil |45 and is converted into avapor' state and it passes through the pipe |31 to the evaporator |20which in this instance acts as a condenser and through pipe |39 to thecondenser |36. Air passing over the condenser |29 and condenser |38takes up sensible heat and the vapor in these condensers r'everts to aliquid state and is withdrawn by the pump |53 and forced back into thetank |38 to be reheated and vaporized. Hence it is apparent that thesensible heat may be added to the air to raise the temperature thereofso that the temperature in the room to which air is supplied by the duct|35 may be kept above atmospheric temperature.

It is to be understood that the air conditioners illustrated in thedrawing may be used to supply air to a duct corresponding to the duct |4shown in the aforementioned patent of which this is a division. Andfurther, any one of the control arrangements shown in said patent inconnection with the rooms I1 to 22, inclusive, may Ibe used to controlthe air' discharge from the duct |4. It is also to be understood thatother analogous devices may be vused to bring about the advantageousresults accomplished by this invention.

Hence while I have illustrated and described a selected embodiment of myinvention, it is to be understood that it is capable of variation andmodification and I therefore do not wish to be limited to the precisedetails` set forth but desire to avail myself of such changes andmodifications as fall within the purview of the following claims.

I claim:

1. Air conditioning apparatus comprising a volatile refrigerating systemhaving a first heat exchange element in thermal exchange relationshipwith the air to be conditioned, a second heat exchange element, a firstrefrigerant now connection between said first and second heat exchangeelements providing an unrestricted passage be- As the warm air passesthrough thel relationship with said second heat exchange elel0 ment forcondensing refrigerant vapor therein when cooling of the air by saidfirst heat exchange element is desired, one of said heat exchangeelements being arranged higher than the other whereby liquid refrigerantmay flow by 16 gravity from the higher of said elements to the lower ofsaid elements, and means for elevating liquid refrigerant from the lowerof said elements to the higher of said elements when refrigerant isbeing liquefied in the lower element and vaporized in the upper element.

2. Air conditioning apparatus comprising in combination, a first heatexchange element for either heating or coo-ling air to be conditioned bycondensation or evaporation of a volatile refrigerant, a second heatexchange element, a first unrestricted refrigerant fiow connectionbetween said first and second heat exchange elements, a secondrefrigerant flow connection between said rst and second heat exchangeelements, one of said connections entering said rst heat exchangeelement above the liquid level therein and the other of said connectionsentering said first heat exchange element below the liquid leveltherein, one of said connections entering said second heat exchangeelement above the liquid level therein,

` the other of said connections entering said second heat exchangeelement below the liquid level therein, means for supplying a heatingmedium in thermal exchange relationship to said second heat exchangeelement for vaporizing liquid refrigerant therein when heating of theair by said first heat exchange element is required, means for supplinga cooling medium in thermal exchange relationship with refrigerant vaporin said second heat exchange element for condensing refrigerant vaportherein when cooling of the air by said first heat exchange element isdesired, and means for inducing circulation of liquid refrigerant fromone'of said heat exchange elements to the other of said heat exchangeelements.

3. Air conditioning apparatus comprising in combination, a rst heatexchange element for either heating or cooling air to be conditioned bycondensation or evaporation of a volatile refrigerant, a second heatexchange element, a first refrigerant flow connection between said rstand second heat exchange elements, a second refrigerant flow connectionbetween said first and second heat exchange elements, one of saidconnections entering said rst heat exchange element above the liquidlevel therein and the other of said connections entering said first heatex change element below the liquid level therein, one of saidconnections entering said second heat exchange element above the liquidlevel therein, the other of said connections entering said second heatexchange element below the liquid level therein, means for supplying aheating medium in thermal exchange relationship to said second heat 70exchange element for vaporizing liquid refriger ant therein when heatingof the air by said rst heat exchange element is required, means forsupplying a cooling medium in thermal exchange relationship withrefrigerant vapor in said second heat exchange element for condensingrefrigerant vapor therein when cooling of the air by said rst heatexchange element is desired, means for inducing circulation of liquidrefrigerant from one of said heat exchange elements to the other of saidheat exchange elements, means responsive to the temperature of air forcontrolling the supply of cooling medium to said second heat lexchangeelement when cooling is required, and means responsive to thetemperature of air for controlling the supply of heating medium to saidsecond heat exchange element when heating is required.

WILLIAM GOODMAN.

